My list:
1. Achievements. Yup, I like em. I didn't' think I would, but I do. They are great in Xenoblade as well, but would be better if they were part of a system-wide collection. People like to collect.
2. Customization home screen. Miis' running around is cool, but some different themes would be great. Maybe that Zelda U scene for a background with Zelda sound effects when you click on things. Or a SM3DW theme. Or a creepy Metroid one. Or just a different look for a generic Wii U system. There should be options. People like to customize.
3. A far better classic games system. Wii's Virtual Console was an industry leader. Wii U's lags far behind. There should be a fantastic, easy to navigate classic game library where you can find and play them all. They should also have a team remastering them all with new visuals, sound and presentation. It could all be part of a subscription service where you get the whole catalog for a small monthly or annual fee.
4. A more searchable eshop.
5. A redesign. This is different than the others, but a smaller, cooler gamepad would be better, and a new aesthetic for the system would be cool. I like what they are doing with the N3DS. They should channel some NES or SNES in the look of Wii U.
